Heat pens in recent years have become useful in many fields such as medicine and seismology which require a high speed recording of data for immediate or later analysis. Since the advent of thermally sensitive recording paper, recording instruments need no longer depend upon a supply of ink. Heat pens generally comprise a heated stylus which, when contacting thermally sensitive recording paper, leaves a permanent visual mark. Heat pens, however, even though not dependent on a supply of ink, also are subject to wear and malfunction. Such malfunction may result from the frictional erosion of the heat pen stylus after contacting extensive lengths of recording paper. Heat pens generally available at the present require complete replacement when their stylus has been sufficiently eroded.
The present invention concerns a heat pen with a readily replaceable stylus. Utilizing the heat pen of the present invention, when frictional erosion has caused the stylus to become unsatisfactory, the eroded stylus may be readily replaced without installation of an entire new heat pen.